Fuser member coating composition and processes for providing elastomeric surfaces thereon

ABSTRACT

Fuser members and processes are provided for crosslinked fluorocarbon elastomer surfaces containing a fluorocarbon elastomer and a non-amino crosslinker together with methods for providing a crosslinked fluorocarbon elastomer surface on a fuser member supporting substrate which include mixing together an acid acceptor, an emulsifier, water, and non-amino based crosslinker with a latex fluorocarbon elastomer.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to fuser members and to processesfor providing elastomer surfaces on a substrate. More specifically, thepresent invention relates to members comprised of a substrate andthereover a crosslinked latex fluoroelastomer surface in which memberscan be selected for a supporting substrate useful in electrostatographicprocesses, inclusive of digital processes and devices. The presentinvention provides an environmentally friendly fluorocarbon elastomersurface for a fuser system member with the positive features of havingchemical, physical and thermal stability, along with sufficienttoughness to resist wear and tear.

[0002] The invention dispenses with the additional costs associated withmaterials such as organic solvents and further, dispenses with the needfor their disposal. This helps prevent air pollution and provides anenvironmentally friendly latex fluorocarbon elastomer emulsion. Inaddition, the present invention minimizes the need for functional fusingoils which are normally necessary to prevent toner from adhering to thesurface of the fuser member. Nonfunctional fuser oils would be preferreddue to economic considerations. Moreover, the present invention providesa fusing system member which has sufficient toughness, along withexcellent chemical, physical and thermal stability, and other propertiesallowing for a larger fusing latitude at higher temperatures (400-450°F.) and decrease in the problems associated with hot offset.

[0003] In a typical electrostatographic reproducing apparatus, a lightimage of an original to be copied is recorded in the form of anelectrostatic latent image upon a photosensitive member and the latentimage is subsequently rendered visible by the application ofelectroscopic thermoplastic resin particles which are commonly referredto as toner. The visible toner image is then in a loose powdered formand can be easily disturbed or destroyed. The toner image is usuallyfixed or fused upon a support, which may be the photosensitive memberitself or another support sheet such as plain paper.

[0004] Thermal energy is commonly used for fixing toner images onto asupport member. To fuse electroscopic toner material onto a supportsurface permanently by heat, it is usually necessary to elevate thetemperature of the toner material to a point at which the constituentsof the toner material coalesce and become tacky. This heating causes thetoner to flow to some extent into the fibers or pores of the supportmember. Thereafter, as the toner material cools and solidifies, itbecomes firmly bonded to the support.

[0005] Typically, the thermoplastic resin particles are fused to thesubstrate by heating to a temperature of between about 90° C. to about200° C. or higher depending upon the softening range of the particularresin used in the toner. It is undesirable, however, to increase thetemperature of the substrate substantially higher than about 250° C.because of the tendency of the substrate to discolor or to catch fire atsuch elevated temperatures, particularly when the substrate is paper.

[0006] Several approaches for accomplishing thermal fusing ofelectroscopic toner images have been described. These methods includeproviding the application of heat and pressure substantiallyconcurrently by various means, such as by a roll pair maintained inpressure contact, a belt member in pressure contact with a roll, andother equivalent means recognized in the art. Heat may be applied byheating one or both of the rolls, the plate members or belt members.Fusing of the toner particles takes place when the proper combination ofheat, pressure and contact time is provided. Various strategies forbalancing these parameters to bring about the fusing of the tonerparticles have been described in the art, and it is recognized that theparameters can be adjusted to suit particular machines or processconditions.

[0007] During operation of a fusing system in which heat is applied tocause thermal fusing of the toner particles onto a support, both thetoner image and the support are passed through a nip formed between theroll pair, or plate or belt members. The concurrent transfer of heat andthe application of pressure in the nip affects the fusing of the tonerimage onto the support. It is important in the fusing process that nooffset of the toner particles from the support to the fuser member takeplace during normal operations. Toner particles offset onto the fusermember may subsequently transfer to other parts of the machine or ontothe support in subsequent copying cycles, thus increasing the backgroundor interfering with the material being copied there. The referred to“hot offset” occurs when the temperature of the toner is increased to apoint where the toner particles liquefy and a splitting of the moltentoner takes place during the fusing operation with a portion remainingon the fuser member. The hot offset temperature or degradation of thehot offset temperature is a measure of the release property of the fuserroll, and accordingly, fusing surfaces with a low surface energy whichprovide the necessary release are desirable. To ensure and maintain goodrelease properties of the fuser roll, it has become customary to applyrelease agents to the fuser roll during the fusing operation. Typically,these materials are applied as thin films of, for example, siliconeoils, to prevent toner offset.

[0008] Particularly preferred fusing systems are comprised of a heatedcylindrical fuser roll having a fusing surface that is backed by acylindrical pressure roll forming a fusing nip there-between. A releaseagent donor roll is also provided to deliver release agent to the fuserroll. While the physical and performance characteristics of each ofthese rolls, and particularly of their functional surfaces, are notprecisely the same because of the various characteristics of the fusingsystem desired, the same classes of materials are typically used for oneor more of the rolls in a fusing system in an electrostatographicprinting system.

[0009] In U.S. Pat. No. 5,736,250, the disclosure of which isincorporated by reference in its entirety, there is describedcrosslinked fluorocarbon elastomer surfaces comprising a fluorocarbonelastomer and an amino siloxane and a method for providing a crosslinkedfluorocarbon elastomer surface on a fuser member supporting substratewhich includes mixing together an acid acceptor, an emulsifier, water,and amino siloxane with a latex fluorocarbon elastomer.

[0010] In U.S. Pat. No. 5,166,031, the disclosure of which isincorporated by reference in its entirety, there is illustrated a fusermember comprising a supporting substrate having an outer layer of avolume grafted elastomer which is a substantially uniform integralinterpenetrating network of a hybrid composition of a fluoroelastomerand a polyorganosiloxane, the volume graft having been formed bydehydrofluorination of a fluoroelastomer by a nucleophilicdehydrofluorinating agent, followed by addition polymerization by theaddition of an alkene or alkyne functionally terminatedpolyorganosiloxane and a polymerization initiator, and wherein thefluoroelastomer can be selected from a group consisting ofpoly(-vinylidene fluoride-hexafluoropropylene) and poly(vinylidenefluoride-hexafluoropropylene-tetrafluoroethylene).

[0011] U.S. Pat. No. 5,366,772, the disclosure of which is incorporatedby reference in its entirety, describes an outer layer of a fuser membercomprised of a substantially uniform integral interpenetrating hybridpolymeric network comprised of a haloelastomer, a coupling agent, afunctional polyorganosiloxane and a crosslinking agent. The hybridpolymeric network is formed by the sequential reaction of thehaloelastomer with a dehydrohalogenating agent, reaction with thecoupling agent, condensation with the functional polyorganosiloxane andcrosslinking with the crosslinking agent.

[0012] U.S. Pat. No. 5,370,931, the disclosure of which is incorporatedby reference in its entirety, describes a grafted elastomer which is asubstantially uniform integral interpenetrating network of a hybridcomposition of a fluoroelastomer and a polyorganosiloxane, said grafthaving been formed by dehydrofluorination of said fluoroelastomer by anucleophilic dehydrofluorinating agent, followed by additionpolymerization by the addition of an alkene or alkyne functionallyterminated polyorganosiloxane and a polymerization initiator; andwherein said outer layer contains copper oxide in an amount of fromabout 2 to about 7 weight percent based upon the total weight of saidouter layer.

[0013] U.S. Pat. No. 5,456,987, the disclosure of which is incorporatedby reference in its entirety, describes an intermediate transfer memberhaving a layer comprised of a grafted titamer formed using a couplerhaving at least one pendant silane group.

[0014] U.S. Pat. No. 5,337,129, the disclosure of which is incorporatedby reference in its entirety, describes an intermediate transfer membercomprising a substrate and a coating comprised of integral,interpenetrating networks of haloelastomer, silicon dioxide andoptionally polyorganosiloxane coupled using an amine coupler having atleast one pendant functional group such as silane.

[0015] U.S. Pat. No. 4,399,553, the disclosure of which is incorporatedby reference in its entirety, describes a water-based fluoroelastomercoating composition comprising a fluoroelastomer and an amino silane.

[0016] There is also known a water-based fluoroelastomer coatingcomposition comprising an aqueous fluoroelastomer dispersion blendedwith a polyamine compound (e.g., hexamethylenediamine carbamate,N,N-dicynnamylidene-1,6-hexanediamine) as a vulcanizing agent (cf.DuPont's “Viton,” Bulletin, No. 5, April, 1961).

[0017] Currently, fluorocarbon elastomer substrates have been applied asa thin layer to surfaces using an organic solvent spray or other liquidorganic process. Normally, the fluorocarbon elastomer is first dissolvedin volatile organic solvents, such as acetone, methyl ethyl ketone,methyl isobutyl ketone and the like, to facilitate the deposition of thethin films of fluoroelastomer on the substrates to be coated and toenable the solvent to evaporate into the atmosphere within a reasonableperiod of time. The use of such volatile organic solvents as diluentscan result in air pollution.

[0018] The drawbacks of using organic solvents or other liquid organicprocesses to coat surfaces with fluoroelastomers includes the high costrelative to other coating processes that contain water as the primarysolvent or diluent, associated with the organic solvent and theattendant vapor filters. In addition, as the concern over hydrocarbonair pollution by state and federal governmental agencies and privateinterest groups increases, and as environmental and health regulationson air pollution resulting from volatile organic solvents tighten overtime, a need exists for fuser containing fluoroelastomers on surfacesthat do not result in excessive volatile organic solvent emission.Further, a need exists for the generation of fluoroelastomers such asthe environmentally friendly fluoroelastomers described, wherein thesefluoroelastomers have the desirable properties necessary for a surfacefor a fusing system member, including high toughness, along withexcellent chemical, physical and thermal stability, and propertiesallowing for a decrease in the problems associated with hot offset. Inaddition, there exists a need for a fuser surface which minimizes thenecessity for use of a release agent. These and other needs can beachieved with the present embodiments thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019]FIG. 1 represents a sectional view of a fuser system with a fusermember of an embodiment of the present invention.

SUMMARY OF THE INVENTION

[0020] Aspects of the present invention relate to a latex basedfluorocarbon system crosslinked with a non-amino based crosslinker thatcan also produce coatings with increased thermal stability when comparedto devices crosslinked with amino crosslinked systems.

[0021] In embodiments, the present invention relates to latexfluorocarbon elastomers crosslinked with carbon based crosslinkers,non-amino siloxanes, and methods thereof. In other embodiments, thepresent invention relates to methods for applying crosslinkedfluorocarbon elastomer surfaces on a substrate, reducing the emission ofvolatile organic solvents by dispensing with the need for those volatilesolvents. The crosslinked fluorocarbon elastomers are useful as surfacesfor components in electrostatographic processes, especially xerographicprocesses, including the surfaces of fuser system members, or fusermembers, including donor rolls, belts and other equivalent meansrecognized in the art; pressure rolls, belts and other equivalent meansrecognized in the art; fuser rolls, belts and other equivalent meansrecognized in the art; toner transfer rollers, belts and otherequivalent means recognized in the art; along with intermediate transfercomponents such as intermediate transfer belts.

[0022] The present invention pertains to a fuser system member of anelectrostatographic apparatus. The fuser system member includes asupporting substrate and an environmentally friendly outer surface of acrosslinked hybrid composition containing a latex fluorocarbon elastomerand a non-amino based crosslinker.

[0023] In embodiments, the crosslinker is carbon based, either polymericor non-polymeric. The crosslinker can be an epoxy, most preferably apolyfunctional epoxy having at least two functional groups and either acarbon or a siloxane polymeric backbone, or a combination thereof.Repeating backbone groups can vary in number from about 1 to about 1000with a preferred range of from about 5 to about 45. Hydroxy, alkoxy andhydrofunctional siloxanes and silanes are also included. In particularlypreferred embodiments the crosslinker is siloxane based, eitherpolymeric or nonpolymeric. The crosslinker may be diepoxy ordisilylalkoxy or a combination thereof.

[0024] Examples of crosslinkers include epoxy terminated hydrocarbons,diols, and silanol, methoxy or ethoxy terminated siloxanes, includingthose encompassed by the following formulae:

[0025] wherein n represents the number of segments and is a number forexample between about 2 and about 20, and preferably, n is a numberbetween about 5 and about 10;

[0026] wherein n represents the number of segments and is a number forexample between about 2 and about 20, and preferably, n is a numberbetween about 5 and about 10;

[0027] wherein n represents the number of segments and is a number forexample between about 1 and about 1000, and preferably, n is a numberbetween about 5 and about 45; and

[0028] wherein n represents the number of segments and is a number forexample between about 1 and about 1000, x represents the number ofsegments and is a number for example between about 1 and about 3, R iseither H, CH₃ or (CH₂)_(y)CH₃, and y represents the number of segmentsand is a number between about 1 and about 3. In the case where x is lessthan 3, the remaining of the 3 groups on the Si atom are CH₃.

[0029] In a particularly preferred embodiment the crosslinker has theformula:

[0030] Crosslinkers which are combinations of the formulas describedabove are also within the scope of the invention, in ratios ranging fromabout 1-99 and about 99-1, about 50-70, and from about 30-50.

[0031] In preferred embodiments, examples of latex fluorocarbonelastomers are a copolymer of vinylidene fluoride andhexafluoropropylene, a terpolymer of vinylidene fluoride,hexafluoropropylene and tetrafluoroethylene or a tetrapolymer ofvinylidene fluoride, hexafluoropropylene, tetrafluoroethylene and a curesite monomer. As is known in the art, a cure site monomer is susceptibleto free radical attack and is commonly used in fluoroelastomer peroxidecure systems, e.g., 1-bromo-2,2-difluoroethylene. In other embodiments,the latex fluorocarbon elastomer is a copolymer of vinylidene fluoride,hexafluoropropylene and tetrafluoroethylene, wherein the latexfluorocarbon elastomer has a fluorine content of from about 50 to about71 weight percent; the outer surface of the fuser system member is fromabout 5 to about 250 micrometers thick, most preferably, about 15 toabout 50 micrometers thick, and the supporting substrate is acylindrical roll or an endless, flexible belt. The cylindrical roll maybe aluminum, copper or steel, and the belt may be polyimide.

[0032] In another embodiment, the fuser system member additionallycontains from about 1 to about 10 intermediate layers positioned betweenthe supporting substrate and the outer surface. At least one of theintermediate layers is preferably an elastomer layer such as a siliconeelastomer or an adhesive layer or an epoxy resin or a silane. The outersurface of the fuser system member may vary from about 5 to about 250micrometers thick, most preferably, about 15 to about 50 micrometersthick. Other intermediate layers may be applied to achieve desiredadhesive and/or elastomeric properties and performance objectives suchas to provide conformity, thermal conductivity, or oil boundary layers,or to act as adhesive layers, binding layers, and/or toughness improvinglayers.

[0033] The present invention also relates to a composition of matter andan environmentally friendly process for coating a fuser member supportwith a crosslinked fluorocarbon elastomer outer surface on a fusermember supporting substrate. The process includes the steps of mixing anacid acceptor, an emulsifier and water to form one dispersion; forminganother, separate dispersion comprising an a non-amino polymeric basedcrosslinker; reacting a latex fluorocarbon elastomer with the two seconddispersions to form a homogeneous crosslinked fluorocarbon elastomer;and subsequently providing at least one layer of the homogeneouscrosslinked fluorocarbon elastomer onto said fuser member supportingsubstrate. The layer of homogeneous crosslinked fluorocarbon elastomeron the fuser member supporting substrate may be heat cured, and the acidacceptor is preferably zinc oxide.

[0034] The emulsifier may includeoctylphenoxpolyethoxy-ethanol-polyethylene glycol, sodium laurylsulphateor ammonium laurylsulphate, the crosslinker is preferably siloxanebased, e.g., hydroxysiloxane, hydrosiloxane or epoxy, and the water ispreferably deionized water. In another embodiment, a metal oxide filleris added to the dispersion containing the non-amino polymericcrosslinker, where the metal oxide filler may include iron II oxide,iron III oxide, titanium dioxide or chromium oxide.

[0035] The present invention pertains to a material and anenvironmentally friendly method for providing a crosslinked fluorocarbonelastomer outer surface on a fuser member supporting substrate includingthe steps of mixing an acid acceptor, an emulsifier, water and anon-amino based crosslinker to form a dispersion; adding and reacting alatex fluorocarbon elastomer with the dispersion to form a homogeneouscrosslinked fluorocarbon elastomer; and subsequently providing at leastone layer of the homogeneous crosslinked fluorocarbon elastomer ontosaid fuser member supporting substrate.

[0036] The invention also pertains to an image forming apparatus forforming images on a recording medium including a charge-retentivesurface to receive an electrostatic latent image; a developmentcomponent to apply toner to the charge-retentive surface to develop theelectrostatic latent image to form a developed image on the chargeretentive surface; a transfer component to transfer the developed imagefrom said charge retentive surface to a substrate; and a fusingcomponent to fuse the developed image to said substrate in which thehybrid composition contains a latex fluorocarbon elastomer and anon-amino based crosslinker.

[0037] The present invention pertains to a process for transferring atleast one toned image from a photoconductor element surface includingrolling a heated intermediate transfer roller over the element while thetemperature of the circumferential surface portions of the roller issufficient to sinter the toner particles which form such toned image toeach other, and rolling the heated, toned image bearing roller over thereceiver to transfer the tone image to the receiver in which theintermediate transfer roller includes a crosslinked hybrid compositionof a latex fluorocarbon elastomer and a non-amino based crosslinker.

DETAILED DESCRIPTION OF THE INVENTION

[0038] Aspects of the present invention relate to fuser members, fusermember coatings, and processes for providing elastomeric coatings onfuser members. The present invention relates to members comprised of asubstrate and thereover a latex based fluorocarbon surface crosslinkedwith a non-amino based crosslinker that can produce coatings withincreased thermal stability. Siloxane can be incorporated in the polymermatrix to reduce the surface energy of the coating and for controlledcompatibility, i.e., wetting, with siloxanes which permits the use ofnonfunctional release agents. Because the process differs from othersemploying quantities of volatile carbon solvent effluent, the processfor formulating the latex based fluorocarbon crosslinked system greatlyreduces the levels of volatile carbon solvent effluent released into theenvironment. Levels are reduced both in the process of preparing thecoating formulation and in the process of coating substrates with thecoating. The processes are both environmentally friendly andcost-effective.

[0039] The present invention relates to a fuser system member having anouter layer comprising a crosslinked composition derived from a latexfluorocarbon elastomer and non-amino polymeric based crosslinker.

[0040] A known fusing system is comprised of fusing system members,including a supporting substrate such as a heated cylindrical fuserroll, film or belt having a fusing outer surface which is backed by acylindrical pressure roll forming a fusing nip there-between. A releaseagent donor roll is also provided to deliver release agent to the fuserroll. While the physical and performance characteristics of each ofthese fusing system members, and particularly of their surfaces are notprecisely the same depending on the various characteristics of thefusing system desired, the same classes of materials are typically usedfor one or more of the rolls in a fusing system in anelectrostatographic printing system.

[0041] The present invention enables surfaces as described inconjunction with a fuser assembly as shown in FIG. 1 where the numeral 1designates a fuser roll comprising fluorocarbon elastomer surface 2 upona suitable base member 4, a hollow cylinder or core fabricated from anysuitable metal, such as aluminum, anodized aluminum, steel, nickel,copper, and the like, having a suitable heating element 6 disposed inthe hollow portion thereof which is coextensive with the cylinder.

[0042] Backup or pressure roll 8 cooperates with fuser roll 1 to form anip or contact arc 10 through which a copy paper or other substrate 12passes such that toner images 14 thereon contact fluorocarbon elastomersurface 2 of fuser roll 1. As shown in FIG. 1, the backup roll 8 has arigid steel core 16 with an fluorocarbon elastomer surface or layer 18thereon. Sump 20 contains polymeric release agent 22 which may be asolid or liquid at room temperature, but it is a fluid at operatingtemperatures.

[0043] In the embodiment shown in FIG. 1 for applying the polymericrelease agent 22 to fluorocarbon elastomer surface 2, two release agentdelivery rolls 17 and 19 rotatably mounted in the direction indicatedare provided to transport release agent 22 to fluorocarbon elastomersurface 2. Delivery roll 17 is partly immersed in the sump 20 andtransports on its surface release agent from the sump to the deliveryroll 19. By using a metering blade 24, a layer of polymeric releasefluid can be applied initially to delivery roll 19 and subsequently tofluorocarbon elastomer 2 in controlled thickness ranging fromsubmicrometer thickness to a thickness of several micrometers of releasefluid. Thus, by metering device 24, about 0.1 to about 2 micrometers orgreater thicknesses of release fluid can be applied to the surface offluorocarbon elastomer 2.

[0044] Generally, in the process for forming the fuser system membersurface, the latex fluorocarbon elastomer is added last. Initially, twodispersions can be formed and subsequently, the latex fluorocarbonelastomer added. Alternatively, a single dispersion is formed andsubsequently, the latex emulsion is added.

[0045] If using two separate dispersions, an acid acceptor and anemulsifier or surfactant are added initially with water to make onedispersion. Curing and crosslinking agents (non-amino polymeric based)can then be mixed with optional fillers and pigments to form anotherseparate dispersion. The latex fluorocarbon elastomer is then addedtogether with the above two dispersions with gentle stirring. Ananti-foaming agent such as Dow Corning 65 additive—a water basedsilicone anti-foam additive (Dow Corning Corporation, Midland Mich.48686) or the equivalent—can be added.

[0046] An alternative and one preferred method is to mix together withgentle stirring an acid acceptor (a basic metal oxide), water,emulsifier, and curing and crosslinking agents (non-amino polymericbased). The dispersion can be allowed to cool before addition of thelatex fluorocarbon elastomer. Next, the resulting dispersion is eitherallowed to air dry or cured in order to evaporate the water, and is postcured with heat.

[0047] A latex fluorocarbon elastomer is used in the present invention.The term latex is intended to include a water-based stabilizeddispersion of an elastomeric compound. The term latex also includes anessentially aqueous mixture e.g., one which lacks an organic solventmedium. Examples of suitable latex fluorocarbon elastomers includecopolymers of vinylidene fluoride and hexafluoropropylene; tetrapolymersof vinylidene fluoride, hexafluoropropylene and tetrafluoroethylene; andtetrapolymers of vinylidene fluoride, hexafluoropropylene andtetrafluoroethylene and a cure site monomer. It is preferred that thelatex fluoroelastomers have a fluorine content of from about 50 to about71 percent by weight. Specific latex fluoroelastomers are manufacturedand are commercially available from Ausimont of Morristown, N.J.,including TECNOFLON TN (having 70% solids by weight). The amount oflatex fluoroelastomer used to provide the surface of the presentinvention is dependent on the amount necessary to form the desiredthickness of the layer or layers of surface material. The solids contentof the final latex fluoroelastomer is from about 10 to about 70 weightpercent, preferably from about 50 to about 60 weight percent. Theselected fluoroelastomer content can be readily obtained byconcentration or dilution. When desired, the latex fluoroelastomer maycontain any conventional additive such as a pigment, an acid acceptor ora filler in addition to the fluoroelastomer.

[0048] The latex fluoroelastomer of the present invention is crosslinkedwith a non-amino based crosslinker which may be a carbon or a siloxanebased crosslinker such as hydroxysiloxane, hydrosiloxane or epoxy.

[0049] Examples of crosslinkers include epoxy terminated hydrocarbons,diols, and silanol, methoxy or ethoxy terminated siloxanes, includingthose encompassed by the following formulae:

[0050] wherein n represents the number of segments and is a number forexample between about 2 and about 20, and preferably, n is a numberbetween about 5 and about 10;

[0051] wherein n represents the number of segments and is a number forexample between about 2 and about 20, and preferably, n is a numberbetween about 5 and about 10;

[0052] wherein n represents the number of segments and is a number forexample between about 1 and about 1000, and preferably, n is a numberbetween about 5 and about 45;

[0053] wherein n represents the number of segments and is a number forexample between about 1 and about 1000, x represents the number ofsegments and is a number for example between about 1 and about 3, R iseither H, CH₃ or (CH₂)_(y)CH₃, and y represents the number of segmentsand is a number between about 1 and about 3.

[0054] In a particularly preferred embodiment, the crosslinker has theformula:

[0055] One such crosslinker is called DC Z 6040 Glycidoxypropyltrimethoxysilane and is produced by Dow Corning Corporation, Midland,Mich. 48686.

[0056] While not wishing to be bound by theory, it is hypothesized thattrace amounts (or more) of hydrofluoric acid present in the latexfluorocarbon elastomer system activate the epoxy functional group. Thisactivated epoxy group attacks the tertiary carbon in the fluorocarbonelastomer chain, followed by a double bond rearrangement, therebyinitiating the nucleophilic addition reaction. The reaction continuesunder additional heat, thus, a crosslinked network is formed.

[0057] In preferred embodiments, the latex fluorocarbon elastomer is acopolymer of vinylidene fluoride and hexafluoropropylene, a terpolymerof vinylidene fluoride, hexafluoropropylene and tetrafluoroethylene or atetrapolymer of vinylidene fluoride, hexafluoropropylene,tetrafluoroethylene and a cure site monomer. In a particularly preferredembodiment, the latex fluorocarbon elastomer is a copolymer ofvinylidene fluoride, hexafluoropropylene and tetrafluoroethylene. Thelatex fluorocarbon elastomer has a fluorine content of from about 50 toabout 71 weight percent.

[0058] The outer surface of the fuser system member is from about 5 toabout 250 micrometers thick, preferably about 15 to about 50 micrometersthick. The supporting substrate may be a cylindrical roll or an endless,flexible belt. The cylindrical roll may be aluminum, copper or steel. Ina particularly preferred embodiment, the belt is polyimide.

[0059] In other embodiments, the fuser system member contains from about1 to about 10 intermediate layers positioned between the supportingsubstrate and the outer surface. At least one of the intermediate layersmay be an elastomer layer such as a silicone elastomer or an adhesivelayer, for example, an epoxy resin or a silane. The outer surface of thefuser system member is from about 5 to about 250 micrometers thick, mostpreferably about 15 to about 50 micrometers thick.

[0060] The invention also relates to methods for providing anenvironmentally friendly crosslinked fluorocarbon elastomer outersurface on a fuser member supporting substrate. The method includes thesteps of mixing an acid acceptor, an emulsifier and water to form onedispersion; forming another separate dispersion comprising an anon-amino based crosslinker; and reacting a latex fluorocarbon with thetwo dispersions to form a homogeneous crosslinked fluorocarbonelastomer. The method may also include the step of providing at leastone layer of the homogeneous crosslinked fluorocarbon elastomer onto afuser member supporting substrate.

[0061] An emulsifier or surfactant may be added in order to form adispersion. In addition, the emulsifier functions to provide increaseddispersion of the fillers, acid acceptor, and curing and crosslinkingagents. Examples of suitable emulsifiers include sodium laurylsulphate,potassium laurylsulphate, ammonium laurylsulphate, or preferablyTriton.RTM.X-100 (octylphenoxypolyethoxy-ethanol-polyethylene glycol)manufactured by Union Carbide Chemicals & Plastics Company, Inc., ofDanbury, Conn. The emulsifier is added in various effective amounts, forexample, an amount of from about 1 to about 10 parts per hundredfluorocarbon polymer with the preferred range being from about 1 toabout 3 parts per hundred fluorocarbon elastomer.

[0062] Although any type of water may be used, e.g., tap water, purifiedwater such as single, double, and triple distilled water, and deionizedwater, it is preferred that ambient deionized water of at least one megohm purity be used. The amount of water added is preferably equal to thetotal amount by weight of the acid acceptor and emulsifier, and is addedin an amount of from about 2 to about 20 parts per hundred of elastomer.

[0063] Other adjuvants and fillers may be incorporated in thefluorocarbon elastomer in accordance with the present invention providedthey do not substantially affect the integrity of the latex fluorocarbonelastomer. Such fillers normally encountered in the compounding offluorocarbon elastomer include coloring agents, reinforcing fillers,alumina or other additives to increase thermal conductivity andprocessing aids. Oxides such as copper oxides may be added in certainamounts to the coatings of fuser members to provide sufficient anchoringsites for functional release oils, and thereby allow excellent tonerrelease characteristics from such fuser members. However, the presentinvention provides an outer layer of a fuser member, wherein the outerlayer has exceptional release properties. Therefore, little or nofunctional fuser oil (having substantially no chemical reactivity) maybe necessary. Optional reinforcing fillers may be added prior toaddition of the latex fluorocarbon elastomer. Specific examples ofpreferred fillers include fillers having a pH of from about 5 to about8. Examples of suitable fillers such as pigments include, for example,zinc oxide, iron II and iron III oxide, titanium dioxide and chromiumoxides. Other suitable fillers include clays and silicates such ascalcium metasilicate or Neuburg clay. The fillers can be added in anamount of from about 1 to about 40 parts per hundred fluorocarbonelastomer with preferred being from about 25 to about 30 parts perhundred fluorocarbon elastomer.

[0064] The latex fluorocarbon elastomer may be applied to a substrate byspraying, dipping, flow coating, silk screening, or equivalent methodsrecognized in the art. The coating is first air-dried and then heatcured (crosslinked). The air drying time may be from about 30 minutes toabout 48 hours, preferably from about 1 to about 24 hours. Thetemperature for air-drying may be from about 20 to about 60° C.,preferably from about 40 to about 50° C. The fluorocarbon elastomer maybe subsequently heat cured. The heat curing time may be from about 30minutes to about 24 hours, preferably from about 1 to about 6 hours, andmost preferably from about 1 to about 2 hours. The temperature of theheat cure may be from about 25° to about 150° C., preferably from about50° to about 100° C., and most preferably from about 60° to about 90° C.The post curing can be at a temperature of from about 100° to about 250°C. and at a time of from about 1 hour to about 24 hours. The preferredpost curing time is for about 1 hour at a temperature of about 250° C.

[0065] The outer surface of the latex fluorocarbon elastomer ispreferably from about 5 to about 250 and preferably about 15 to about 50micrometers thick. This range is selected because it provides a layerthin enough to prevent a large thermal barrier for fusing, whileproviding a layer thin enough to allow a reasonable wear life.

[0066] The fluorocarbon elastomer produced by this process may beevaluated with ASTM F219 using the Instron 1122 (American Society forTesting of Materials)

[0067] The fuser system member substrate on which the latex fluorocarbonelastomer is coated may be a roll, belt, flat surface or other suitableshape used in the fixing of thermoplastic toner images to a suitablesubstrate. It may take the form of a cylindrical sleeve, a drum, a beltor an endless belt. Specific examples of the fuser system member includea fuser member, a pressure member, a release agent donor member,preferably in the form of a cylindrical roll such as, for example, afuser roll, a donor roll and a pressure roll. It may also take the formof an intermediate transfer belt. Typically, the fuser system member ismade of a hollow cylindrical metal core, such as copper, aluminum,steel, or certain plastic materials chosen to maintain rigidity,structural integrity, as well as being capable of having the crosslinkedfluoropolymer coated thereon and adhered firmly thereto. In oneembodiment, the core, which may be an aluminum cylinder, is degreasedwith a solvent and cleaned with an abrasive cleaner prior to beingprimed with a primer, such as Dow Corning 1200, which may be sprayed,brushed or dipped, followed by air drying under ambient conditions forthirty minutes and then baked at approximately 150° C. for about 30minutes.

[0068] Alternatively, there may be one or more, and possibly up to 10intermediate layers between the substrate and the outer layer of thecrosslinked fluoroelastomer. Optional intermediate adhesive layersand/or elastomer layers may be applied to achieve desired properties andperformance objectives of the present invention. An adhesive layer maybe selected from a polymeric compound, for example, epoxy resins,silanes and polysiloxanes. Preferred adhesives are proprietary materialssuch as Union Carbide A-1100, Dow TACTIX 740, Dow TACTIX 741, and DowTACTIX 742. A particularly preferred curative for the aforementionedadhesive is DOW TACMX 741 and 742, available from Dow Chemical Company.

[0069] Typical elastomer layers include materials having thermal andmechanical properties appropriate for such layers, such as siliconeelastomers and fluoroelastomers. The thickness of the intermediate layeris from about 5 to about 250 micrometers, preferably about 15 to about50 micrometers, depending on the required thermal conductivity and otherphysical properties required for any particular system. A siliconeelastomer intermediate layer may be applied according to conventionaltechniques such as injection molding and casting after which it is curedfor up to 15 minutes and at about 120 to about 180° C. to provide acomplete cure without a significant post cure operation. This curingoperation should be substantially complete to prevent debonding of thesilicone elastomer from the core when it is removed from the mold.Thereafter, the surface of the silicone elastomer is sanded to removethe mold release agent and it is wiped clean with a solvent such asisopropyl alcohol to remove all debris. The present fluorocarbonelastomer surfaces are also suitable for use with intermediate transfercomponents such as an intermediate transfer belt. Examples ofintermediate transfer members are found in U.S. Pat. No. 5,110,702, thedisclosure of which is hereby incorporated by reference in its entirety.This patent discloses non-electrostatic transfer of a toner image usinga roll as an intermediate transfer member. Examples of intermediatetransfer members are also found in U.S. Pat. No. 3,893,761, thedisclosure of which is hereby incorporated by reference in its entirety.This patent discloses an intermediate transfer belt having a polyimidefilm substrate coated with a silicone rubber or a fluoroelastomer. Otherexamples of intermediate transfer components are found in U.S. Pat. Nos.4,684,238; 4,690,539; 4,684,238; 4,690,539; 5,119,140; 5,099,286; and5,150,161, the disclosures of which are hereby incorporated by referencein their entirety.

[0070] The resulting fuser system member surface comprises a crosslinkedfluorocarbon elastomer that is comprised of a latex fluorocarbonelastomer crosslinked with a non-amino polymeric based crosslinker. Inembodiments, the crosslinked fluoroelastomer is a substantially uniformintegral interpenetrating network of a hybrid composition, wherein boththe structure and the composition of the latex elastomer and thecrosslinking agent are substantially uniform when taken throughdifferent slices of the fuser member or intermediate belt member.

[0071] All patents, applications, references and other documentsreferred to herein are hereby specifically, and totally incorporatedherein by reference in their entirety in the instant specification. Theappropriate components, processes, and method thereof of these patentapplications and other documents may be selected for the presentinvention and embodiments thereof

[0072] The invention is further illustrated by the followingnon-limiting examples. Unless otherwise indicated, all parts andpercentages are by weight.

EXAMPLE I Preparation of Latex Emulsion/Dispersion

[0073] A general but not exclusive approach for preparation of a latexemulsion is to prepare two or more ingredient dispersions and add themto the latex emulsion. For example, an acid acceptor and an emulsifierare mixed into an approximately equal weight of deionized water to forma dispersion. Fillers and curatives are mixed in the same manner to formanother dispersion. These two dispersions are then slowly stirred intothe latex containing fluoroelastomer, to which an antifoaming agent maybe added. This combined dispersion is then ready for coating.

[0074] More specifically, fifty grams (10 parts per hundred polymer) ofacid acceptor such as zinc oxide, for example zinc oxide from Aldrich,catalog number 20,553-2, and five grams (1 part per hundred polymer) ofan emulsifier or surfactant, for example, emulsifier dodecyl sulfate,sodium salt, Aldrich catalog number 86201-0, are added to fifty grams(10 parts per hundred polymer) of deionized water in a glass bottle androlled twenty four hours on a roll mill. Twenty grams of this dispersionare slowly stirred into 145 grams of a well dispersed TN Latex Tecnoflonfrom Ausimont. Twenty grams (20 parts per hundred fluoroelastomer)crosslinker and one half gram (0.5 parts per hundred polymer) of anantifoaming agent such as BYK 3105 from BYKCHEMIE are then slowly addedwith thorough mixing to the TN Latex dispersion. The final dispersion isthen ready for coating a substrate. The coating is oven dried for 1 hourand 45 minutes at 130° F., 54° C., and is cured and post cured for 18hours at 194° F., 90° C. The resulting layer was determined to be acrosslinked latex fluoroelastomer/polydimethylsiloxane surface.

EXAMPLE 2 Effects of Process Conditions on Latex FluoroelastomerCoatings

[0075] Three samples of the non-amino polymeric based crosslinkedformulations from Example 1 are prepared. Samples A and C are driedaccording to Example 1, and sample B is dried overnight at ambienttemperature. Both A and B are then cured and post cured for 16 hours atabout 200° F., 93° C., while C is cured/post cured for 16 hours at about400° F., 204° C. Bubble formation in the sample can be used as thecriterion for quality measurement, in that little or no bubble formationdemonstrates good workable quality. For purposes of illustration, othercharacteristics of good workable quality include good consistency and noapparent, substantial separation of components within at least a timeframe adequate to employ the method and/or apply the coating of thepresent invention.

EXAMPLE 3 Evidence of Crosslinking in Latex Fluroelastomer Coatings

[0076] Two samples, differing only in the respect that one contains thenon-amino polymeric based crosslinker and the other contains nocrosslinker, are prepared, coated, dried, cured and post cured accordingto the procedures outlined in Example 1. Both samples are soaked in2-butanone, overnight. The crosslinked sample will not dissolve whilethe control, the non-crosslinked sample, will completely dissolve, thusevidencing that crosslinking does not occur unless a crosslinker isadded.

EXAMPLE 4 Coating Fuser Member for Use in Electrophographic Processes

[0077] A formulation as in Example 1 or 2 is coated onto a multi-layerfuser member by a flow-coating or spray process, and then curedaccording to the schedule outlined in those examples. The multi-layerfuser member is comprised of a metal core, such as stainless steel oraluminum, onto which an adhesive layer is added. The outermost layer ofthe fuser member is a coating according to the invention. Theformulation may also include carbon black or other filler to impartthermal conductivity to the material. The multi-layer roll is then usedas a fuser member in an electrophotographic process.

1. A component comprising a substrate and a hybrid compositioncomprising a latex fluorocarbon elastomer and a non-amino basedcrosslinker.
 2. A component in accordance with claim 1, wherein saidcrosslinker is selected from the group consisting of carbon and siloxanebased crosslinkers.
 3. A component in accordance with claim 2, whereinsaid siloxane based crosslinker is selected from the group consisting ofhydroxysiloxanes, hydrosiloxanes and epoxys.
 4. A component inaccordance with claim 2, wherein said crosslinker is selected from thegroup consisting of diepoxy and disilylalkoxy based crosslinkers andcombinations thereof.
 5. A component in accordance with claim 3 whereinthe crosslinker is a polyfunctional epoxy having at least two functionalgroups and a polymeric backbone of carbon, siloxane, or a combinationthereof.
 6. A component in accordance with claim 2 wherein said carbonbased crosslinker is selected from the group consisting of epoxyterminated hydrocarbons and diols.
 7. A component in accordance withclaim 2 wherein said siloxane based crosslinker is selected from thegroup consisting of silanol, methoxy and ethoxy terminated siloxanes. 8.A component in accordance with claim 1, wherein said crosslinker is

wherein n represents the number of segments and is a number betweenabout 2 and about
 20. 9. A component in accordance with claim 8 whereinn represents the number of segments and is a number between about 5 andabout
 10. 10. A component in accordance with claim 1, wherein saidcrosslinker is

wherein n represents the number of segments and is a number betweenabout 2 and about
 20. 11. A component in accordance with claim 10wherein n represents the number of segments and is a number betweenabout 5 and about
 10. 12. A component in accordance with claim 1,wherein said crosslinker is

wherein n represents the number of segments and is a number betweenabout 1 and about
 1000. 13. A component in accordance with claim 12wherein n represents the number of segments and is a number betweenabout 5 and about
 45. 14. A component in accordance with claim 1,wherein said crosslinker is

wherein n represents the number of segments and is a number betweenabout 1 and about 1000, x is a number between about 1 and about 3, R iseither H, CH₃ or (CH₂)_(y) CH₃, and y is a number between about 1 andabout
 3. 15. A component in accordance with claim 14 wherein nrepresents the number of segments and is a number between about 5 andabout
 45. 16. A component in accordance with claim 1 wherein thecrosslinker is


17. A component in accordance with claim 1, wherein the fluorocarbonelastomer is selected from the group consisting of: a) copolymers ofvinylidene fluoride and hexafluoropropylene; b) terpolymers ofvinylidene fluoride, hexafluoropropylene and tetrafluoroethylene; and c)tetrapolymers of vinylidene fluoride, hexafluoropropylene,tetrafluoroethylene and cure site monomer.
 18. A component in accordancewith claim 1, wherein the fluorocarbon elastomer is selected from thegroup consisting of terpolymers of vinylidene fluoride,hexafluoropropylene and tetrafluoroethylene.
 19. A component inaccordance with claim 18, wherein the fluorine content of thefluorocarbon elastomer is from about 50 to about 80 weight percent. 20.A component in accordance with claim 1, wherein hybrid composition isfrom about 15 to about 50 micrometers thick.
 21. A component inaccordance with claim 1, wherein said substrate is a cylindrical roll.22. A component in accordance with claim 21, wherein said roll isselected from the group consisting of aluminum, copper and steel.
 23. Acomponent in accordance with claim 1, wherein said substrate is anendless, flexible belt.
 24. A component in accordance with claim 23,wherein said substrate is comprised of polyimide.
 25. A component inaccordance with claim 24, said substrate further comprising from about 1to about 10 intermediate layers positioned between the substrate and thehybrid composition.
 26. A component in accordance with claim 25, whereinat least one of the intermediate layers is an elastomer layer or anadhesive layer.
 27. A component in accordance with claim 26, whereinsaid intermediate layer is an elastomer layer comprising a siliconeelastomer.
 28. A component in accordance with claim 27, wherein saidintermediate layer is an adhesive layer comprising a polymeric compoundselected from the group consisting of epoxy resins and silanes.
 29. Acomponent in accordance with claim 25, wherein at least one of theintermediate layers comprises a crosslinked hybrid composition, saidhybrid composition comprising a latex fluorocarbon elastomer and anon-amino based crosslinker.
 30. A method which comprises the steps of:mixing an acid acceptor, an emulsifier and water to form a dispersion;providing a non-amino polymeric based crosslinker; reacting a latexfluorocarbon elastomer with said dispersion and the non-amino polymericbased crosslinker to form a crosslinked fluorocarbon elastomer; andproviding at least one layer of the crosslinked fluorocarbon elastomeronto a substrate having an outer surface.
 31. A method in accordancewith claim 30, further comprising the step of heat curing the layer ofcrosslinked fluorocarbon elastomer on the outer surface of saidsubstrate.
 32. A method comprising the steps of: mixing an acidacceptor, an emulsifier, water and a non-amino based crosslinker to forma dispersion; adding and reacting a latex fluorocarbon elastomer withsaid dispersion to form a crosslinked fluorocarbon elastomer; andproviding at least one layer of the crosslinked fluorocarbon elastomeronto a fuser member supporting substrate.
 33. A method in accordancewith claim 32, wherein said crosslinker is selected from the groupconsisting of carbon based polymeric crosslinkers and siloxane basedpolymeric crosslinkers.
 34. A method in accordance with claim 33,wherein said siloxane based croslinker is selected from the groupconsisting of hydroxysilanes and epoxys.
 35. A method in accordance withclaim 33, wherein said crosslinker is selected from the group consistingof diepoxy and disilylalkoxy based crosslinkers and combinationsthereof.
 36. A method in accordance with claim 33, wherein saidcrosslinker is selected from the group consisting of:

wherein n represents the number of segments and is a number betweenabout 2 and about
 20. 37. A method in accordance with claim 36, whereinn represents the number of segments and is a number between about 5 andabout
 10. 38. A method in accordance with claim 33, wherein thecrosslinker is selected from the group consisting of:

wherein n represents the number of segments and is a number betweenabout 1 and about 1000, x is a number between about 1 and about 3, R iseither H, CH₃ or (CH₂)_(y) CH₃, and y is a number between about 1 andabout
 3. 39. A method in accordance with claim 38, wherein n representsthe number of segments and is a number between about 5 and about
 45. 40.A method in accordance with claim 32, wherein the crosslinker is:


41. A method in accordance with claim 32, wherein said latexfluorocarbon elastomer is selected from the group consisting of:copolymers of vinylidene fluoride and hexafluoropropylene; terpolymersof vinylidene fluoride, hexafluoropropylene and tetrafluoroethylene; andtetrapolymers of vinylidene fluoride, hexafluoropropylene,tetrafluoroethylene and cure site monomers.
 42. A method in accordancewith claim 32, wherein said latex fluorocarbon elastomer is selectedfrom a group consisting of terpolymers of vinylidene fluoride,hexafluoropropylene and tetrafluoroethylene.
 43. A method in accordancewith claim 32, wherein said acid acceptor is zinc oxide.
 44. A method inaccordance with claim 32, wherein said emulsifier is selected from thegroup consisting of octylphenoxpolyethoxy-ethanol-polyethylene glycol,sodium laurylsulphate and ammonium laurylsulphate.
 45. A method inaccordance with claim 32, further comprising the step of adding a metaloxide filler to said non-amino crosslinker dispersion.
 46. A method inaccordance with claim 45, wherein said filler is selected from the groupconsisting of copper oxide, iron oxide and aluminum oxide.
 47. A methodin accordance with claim 32, further comprising the step of adding apigment to said non-amino crosslinker dispersion.
 48. A method inaccordance with claim 47, wherein said pigment is selected from thegroup consisting of iron II oxide, iron III oxide, titanium dioxide andchromium oxides.
 49. A method in accordance with claim 32, wherein saidwater is deionized water.
 50. A method in accordance with claim 32,further comprising the step of heat curing the layer of crosslinkedfluorocarbon elastomer on the outer surface of said fuser membersupporting substrate.
 51. An apparatus comprising: a charge-retentivesurface; a development component to apply toner to said charge-retentivesurface to develop said electrostatic latent image to form a developedimage on said charge retentive surface; a transfer component to transferthe developed image from said charge retentive surface to a substrate;and a fusing component to fuse the developed image to said substrate,wherein said fusing component comprises a supporting substrate and anenvironmentally friendly outer surface thereon comprising a crosslinkedhybrid composition, wherein said hybrid composition comprises a latexfluorocarbon elastomer and an a non-amino based crosslinker.
 52. Anapparatus in accordance with claim 51, wherein said crosslinker isselected from the group consisting of carbon based crosslinkers andsiloxane based crosslinkers.
 53. An apparatus in accordance with claim51 wherein said charge retentive surface is adopted to receive anelectrostatic latent image thereon.
 54. A process for transferring atleast one toned image from a photoconductor element surface to areceiver comprising: rolling a heated intermediate transfer roller overthe element while the temperature of the circumferential surfaceportions of the roller is sufficient to sinter the toner particlescomprising said toned image to each other; and rolling the heated, tonedimage bearing roller over the receiver to transfer the tone image tosaid receiver, wherein said intermediate transfer roller comprises acrosslinked hybrid composition, said hybrid composition comprising alatex fluorocarbon elastomer and a non-amino based crosslinker.
 55. Afuser system member in accordance with claim 54, wherein saidcrosslinker is selected from the group consisting of carbon basedcrosslinkers and siloxane based crosslinkers.
 56. A fuser membercomprising a substrate having a hybrid composition coating thereon, saidhybrid composition coating comprising a latex fluorocarbon elastomer anda non-amino based crosslinker.